President Trump's coal nation is facing a tough end to the year as U.S. coal production sank to an all-time low in the final week of 2017 as the Christmas holiday and bitter-cold temperatures added to the long-term trends pummeling the industry.

That was down 28 percent from the same week in 2016 and the lowest tally in records dating to 1992.

As Bloomberg notes, weekly coal production generally falls at the end of the year as rail and mining crews take time off, said Matt Preston, a North American coal analyst at Wood Mackenzie Ltd. But the drop-off was sharper than ever in 2017 as the industry continued to struggle to compete with natural gas and, to a lesser extent, wind and solar farms.